Grinding machine



April 7, 1931- R. F. PETERS E'r AL 1,800,102

GRINDING MACHINE Filed June 2.6, 1928 3 Sheets-Sheet l l@ Glen/LL.

A TTORNEY.

April 7, 1931. R. F. PETERS E'r AL GRINDT NG MACHINE Filed June 26, 1928 A 5 Sheets-Sheet 2 I N V ENTOR5 A TTORNE Y.

April 7, 1931. R. F. PETERS ET AL GRINDING MACHINE Filed June 26, 1928 3 Sheets-Sheet 3 INVENTORS JFPeZi/rs BY Glenn/L azds ATTORNEY.

struction,

Patented Apr. 7, 1931 UNTD STATES PATENT OFFlCIz".`

REGINALD I". PETERS AND GLEN N L. DAVIS, 0F SPRINGFIELD, MISSOURI MACHINE Application filed .Tune 2G, 1928. Serial N'o. 288,516.

This inventionrelatesto a grinding machine designed primarily for use in connection with the grinding:` of angle cocks, but it is to be understood that a machine in ac cordance with this invention may be emp eyed; for any purposes for which it is found olicable, and the.` invention has for its objectto provide, in a manner as hereinafter set forth, a machine ofthe class referred to so constructed andfarranged for producing a `uniform product and to meet the need of `renter production at less cost.

` A further obj ect of the invention is to provide, in a manner as hereinafter set forth al machine of the character referred to for simultaneously grinding` a plurality of angle cocks and further for selectively discontinuing the grindiugaction upon one of the angle cocks without discontinuing the grinding action upon the others.

A further object of the invention is to provide. in amanner as hereinafter setforth, a

-machine of the class referred to including means operated from the driving mechanism ofthe machine to provide for an intermittent lifting action for the cocks duringr the grindingr step therefor'.

Further objects of the invention are to provide, in a manner as hereinafter set forth..

a grinding machine for the purpose referred to which is comparatively simple in its construction and arrangement, strong, dura-ble. compact, thoroughly eflieient in its use, providiner foruniform production, readily semhled, and` comparatively inexpensive to `set up and maintain.

p With the foregoing and other objects in view the invention consists ofthe novel concombination and arrangement of parts as hereinafter more specifically doscribed, and illustrated in the accompany ingr drawings, wherein is shown anembodiment of the invention, but it is to be understood that changes, variations and modifications canloe resorted to which fall within the scope of the claims hereunto appended.

In the drawings wherein like reference characters denote corresponding parte tluouglioutthe several vlawsz- Figure l is a front elevation of a grinding machine in accordance with this invention.

Figure 2 is a topplan view thereof.

`Figure 3 a section on line 3 3 Figure 2.

Figure fl is a section on line 4 4 Figure 3.

igure 5 is a section on line 5-5 Figure l.

Figure 6 is au inverted plan of the lift shaft bearing.

Figure 7 is a sectional, elevation of thelift shaft hearing. l i

llipjure 8 is an elevation of one of the spindles.

F igure 9 is a top assembly.

Figure 10 is F euro ll is Figure l2 is plan View of the lifter a side elevation thereof. a sectional plan of the lifter. a sectional detail illustrating i a keeper.

a sectional plan of the clutch The legs o of the base of plate l and the legs 2 are arranged at a point removed inwardly with respect to the other end of the base or plate l. The legs 2, terminate in `or secured with a rectangular platform 4, formed with a lengthwise extending chamber 5 corresyfiond ing to the length of the liilatform 4l and openingr at one side and at each end of the latter. The top wall of the chamber 5 has the major portion, indicated at 6 positioned ahove the remainingf part thereof as indicated at 7. The bottom wall of the chamber `5 has the major portion thereof, indicated at 8 positioned below the remaining part thereof indicated at 9. The parts 7 and 9 oppose each other, as well as the parts 6 and 8. In transverse section the length of the top and bottom walls of the chamber 5 is such as to extend from the front side to beyond, the lon-` gitudinal median of the platform 4.

`The platform 4,- is formed with a setcf yare secured to the platform 4 holdfast devices 18. The plate 17 is formed spaced openings 10 and with the set extending lengthwise of the platform. The openings 10 communicate with the chamber 5 through the part 6 of the top wall of the latter. The outei` ends of the openings 10 are positioned at the upper face of the plati form 4.

The lower part of platform 4 is provided with a set of spaced openings-11 and with the set disposed longitudinally ofthe platform and with the openings of the set 11 of greater diameter than the openings 10. The openings 11 are arranged below and aligned with the openings 10. The walls of the openings 11 are threaded. rlhe openings 11 com-V municate with the chamber 5 and extend through the part 8 of the bottom wall of said chamber. The lower face of the platform 4 is provided with spaced bosses 12 through which the openings 11 extend.

The platform 4 between the top and bottom thereof is provided with a longitudinal` ly `extending slot 13 which communicates vwith the chamber 5 and opens at that side of the platform 4 opposite the side in which the chamber 5 opens. The slot 13 is of materially less length than the length of the platform 4 and is positioned centrally of the latter.

Secured to the platform 4, as well as depending therefrom is a plate 13 which closes the" outer side of the chamber 5. The plate 13 is detachably secured in position by holdlfast devices 14,15.- The ends of the chamber 5 are closed by plates 16 and -17 and which with an opening 19 for a purpose to be .presently referred to, and saidV opening aligns with theinner side of the chamber 5 at the j rear end thereof. The parts 7 and 9 of the top and bottom walls respectively of the chamber 5 provide guiding means for a reciprocatory element to be presently referred e to. Extending from the plate 1 7 is a guard member 2O for a purpose to be presently referred to.

rlhat side of the platform 4 to which is secured the closure plate 13, isvtermed the front of the machine.

Mounted on thebase or plate 1, adjacent the legs 2, is a prime mover, in the forni of a motor 21 having its shaft 22 provided with a pinion 23. Positioned adjacent to and rearwardly ofthe legs 21s a stationary guard orrgear case 24 for the pinion 23 and also for a gear wheel 25 which meshes with and is driven from the pinion 23. kOne side of the gear 25 isi recessed asat 26 and with the lwall 'of the latter provided at diametrically'dis posed points with "a pair of cam faces 27, 27 The gear 25 is positioned in proximity to the rear of the platform 4 at that end of the platform supported by the legs 2.

The non-recessed face of the gear 25has Vend by suitable l projecting rearwardly therefrom a crank pin 28 to which is attached a connecting rod 29. The rod 29 is connected at one end to the wrist pin 28 and at its other end connected to a wrist pin 30 carried on the outer end of a laterally disposed arm 31 formed on a reciprocatory rack bar 32 which is positioned between the parts 7 and 9 of the top and bottom walls of the chamber v5 and said parts 7 and 9 provide guides for the rack bar 32. The arm 31 extends outwardly through the slot 13 formed in the platform 4. lllhe func tion obtained from the rack bar 32 will be presently referred to. lilixedly secured to the top of the platform 4, at that end of the latter supported by the legs 2, is a bearing 33 for a lift shaft 34. The shaft 34 extends lengthwise with respect to the platform 4 and extends through spaced bearings 35 which are fixedly secured to the top of the platform 4. The'shaft 34 has one thereof extended beyond the bearing 33 and said projecting end, which is indicated at'36 has fixedly secured thereto, by the pin 37, a casting 38 formed with a pin 39, carrying a bearing 4() for a roller 41 which is intermittently engaged by thel cam faces 27 and 27 forthe purpose of rocking the shaft 34 for moving the lifter assembly to be presently referred to. f

The casting 38 projects rearwardly .and at right angles from the shaft 34 and extends into the recess 26 so that the pin 39 and the casting l33 will position the roller 41 in the path of the cam faces 27, 27 see Figure 5. Supported from the platform 4 is al set of grinding mechanisms and the number of the mechanisms of the setV corresponds to the number of openings 10 or 11; The openings 10 and 11 are provided for coupling the grinder mechanisms to the platform and said grinder mechanisms extend above and depend below the platform 4. fis each of the grinder mechanisms is of the same construe` tion but one will be described, as the description of one will apply to 'the other. Each grinder mechanism includes a spindie referred to generally at 42 and it comprises an upper part 43, a pair of intermedi ate parts 44, and a lower part 46. The spindle 42 is of cylindrical cross section and provided with an axial bore 47 extending from end to end thereof. The upper and the lower portions of the bore 47 ,indicated at 48, 49 respectively arev of greater diameter than the remaining portion of the bore. rlhe walls of the parts 48 and 49 of the bore are threaded. The part 43 is of greater length than the'part 49. rlhe partsf43 and 45 of the spindle are ofthe same diameter and the parts 44 land 46 are also ofthe same diameter. rEhe part 44vis interposed between the parts 43, 45 of the spindle. -The part 43 is of greater length than the part 45 and the part 46 is of greater length than the part Vlo .the spindle 412 43..` rllhe part; 441is of lesslength,` than any of they other parts of the spindle. The part 43 at; its` bottom` isfoiunedvivith a laterally eri tending', annular flange. 50;, The` part is rovided Witlr a radical` port51 Whichopens into the" bore 47. The part 46 is provided with a radical port 52 Whichi opens into the bore 4f?. The part 46 `in` proximity to its lower end is ormedwith. a pair of diametrically disposed. peripherallugs 53 which consti-tute keys tor a purpose to be presently ferred to. i

Secured` in theV part49 Ot tlieibore47 and depending from the spindle 42 is a grease cup 54, Secured inA the part 48fof the bore 4Z is a threaded stud 55 for connecting theY valve toA be ground to the spindle 42.

The snindle 42 is of a length to project a substantial distance above and. to depend below. the platform 4..

Surroundingfthe parte: 44 and 45. ofthe spindle 420E belovtthe flange 5,0 isa` beaming sleeve 56 havingwitsupper endprovided with a laterally extending annular flange 5,7 which seats `on the upper-face of the platform 4. The-sleeve 5G is arranged inopenings 10 and has itsdloiver edge flushnithgthe part 6 of the top Wall of, the, chamber-15. The, part 45 of depends below the top wall ot the chamber 5. The partf44 of the spindle `42` provides what may he termed agrinding clearance. Secured; to the threaded Wall of an openingl llis a peripherally threaded bear.- ingl 58, having its lower end." provided Wit-l1 a laterally extendingiannular ilange 59,Which abutsagainst the boss 12,.` The upper end ot the bearing- 58is beveled to provide a point 59` or rather a sharp corner at tlieupper4 `end oi the inner face ofthe liearing.` Secured to the inner tace of the bearing' 5'8is alnishing` 6U. The bushing` corresponds inA lengtl'i to the bearing and the latter extends a, substantial. distance above the part 8 of the lower Wallet the chamber 5'."

Loosely mounted onthepart 46 of the spindle 42 and supported on the top, of the beari'ng and bushing 60i`s apinion G1' provided with a dependinghub 62 of a length to depend below the bearing 58 and; bushing 60. The lower end of the hub 62. is formed` with clutching` teeth 63..

Slid bly mounted on the lower end of the `part 46of`the spindle 42, as Well as .being connected to the latter by the keys 53 is a clutching member 64`having itstop provided With clutching teeth G5 to coact With the teeth 63 for the purpose ot' clutchingthe pinion 61 to the spindle 42.I` The pinion 61'` constitutes a driving means for the spindle 42.` The member 64 is provided on its periphery with an annular flange 65.

Connected to the clutching member 64 is a clutch shiftingcollar 67 Whichis construted in a manner. to. abut. the upper and lower et thetllange whereby the 0.0.1,-

lar Willbe permanently carried by` theclutching member 64. See Figure lith roten ence toFigure 13 the collarincludes a pair of oppositely extending;r sockets SWhich are diametrically disposed and said collar 67 further includes a detachable ring,l 69 which removably securesthe collar to the clutching member (i4. i

Pivotally connected with the collar G7 is a shifting; yoke therefor consisting` ot :1.` body portion 70 provided with a pair ot arms 71 which are oppositely disposed with respect to each; other and which have the collar 67 arranged therebetween. The arms 71 are connected tothe collar G7 by pins 72 which engage in` the sockets 68. The arms 71 ex tend. inwardly from the body portion 7 0 and projecting outwardly therefrom is a handle member (3. The plate 13 is formed With a `slot 7.4 to provide a clearance for the handle member 73. The bodyof the shifting yoke is ar angedy between a` pair of brackets 75` arranged in spaced relation and secured by holdfast devices Ttagainst the inner face of theplatell.

Carried by the` brackets 751 and extendingr through thebody portion 70 ot the shifting' yoke is a pivot 77. for the latter.` Pivotally connected `to the outer face ofthe plate 13, as at 78. is a depending latch 79 adapted to overlap the handle member 73 for latching it in a` positionv to` maintain the clutching member, `(54 in clutching engagement with the hub 62Whereby the pinion 61 will be coupled to the spindle 42 and the latter Willbedriven trom said pinion.

The pinionl is driven from thel recipro* catory rack bar 32 and meshes therewith. The rack bar is of a length to permanently mesh with the pinions G1 ot' the grindingV mechanisms. Then the pinions 61 of the grinding mechanisms are clutched to the spindles 42 of such mechanism, these latter will be simultaneously operate-d, but the clutching means permit of selectivelydiscontinuing the. operation of a grinding mechanism when desired.

Mounted on the top olf each spindle/42 a hollow frusto-conica. combined mechanism protector and drip detlecting member` 78 through which extends the stud 55. Mountedl on the stud is a clamping nut 79 which bears against the top oil the member 78 for liredly securing it in position with respect to the `spindle 42. The member 59 at its lower end is of `greater diameter than the ianges 50 and 5?.

Positioned on the top o t the platform 6 a drip pan 7,9 provided With vertically disposed annular collarsSO for surroinuling,r the abutting flanges. 50 and. 5.7. Thecoliars 8O projectabove the flanges 50,` The members 7 8- extendover the tops of the collars 8O and into the p ani'.` The sdesand erldS ofthe jini o each of which is formed with an opening 83 for the passage of the shaft 34. Holdfast means 84 are provided for securing the arms 82 to the shaft 34. Extending'through the body portion 85 of the V member 81, as Well as threadedly engaging therewith is an ad-l justing screw 86. Carried by the body pors tion 85 is a keeper 87 for the screw 86. Loosely mounted on the shaft 34 between the arms 82 of the V member 81 is alifter member consisting of a stem 88 having a dovvnturned inner portion 89. rlhe stem 88 is formed with an opening 90 for the passage of the shaft 34. Formed integral With the outer end of the Y stem 88 is a pair kof oppositely extending curved arms 91, l92 having upstanding enlargements 93 on the upper face of each arm at the inner end thereof. The dovvnturned portion 89 of the stem 88 is'positioned in the path of the adjusting screw 86, which also acts as a means for rocking the lifting member on the shaft34 to lift the valve housing or body. The length of the lift can be governed by the adjusting of the screv7 86. The arms 91, 92of the lifting member straddle the stud 55, as Well as being spaced therefrom and in this connection see Figure 2.

Connected to the top of the platform 4, upon the front thereof, is a series of stops or'holders for the valve housing or body. The end holders of the set are indicated at 94, 95 and are of inverted L-shape and oppositely disposed With respect to each other. The intermediate holders of the set are indicated at 96 and are of T-shape form. Each holder 96 opposes and is spaced from a bearing 35 as Well asextends above the same. An end holder 95 is positioned to oppose a bearing 35 as Well as lbeing spaced therefrom and eX- tending above the bearing. rlhe endgholder 94 is arranged in opposed relation With respect to the shaft 34 and extends above the same.

The holders are vertically disposed, are arranged in spaced relation and are also spaced from the grinding mechanisms and lifter assemblies.

The bore 47 and ports 51, 52 provide lubricant channels. The pinions 61 are turned to an angle slightly greater than 360o then reversed and turned in the opposite direction.

The construction of the bearings 33 and 35 is best shown in Figure 7 and which consists of a base 97, a shank 98, a vtubular head 99,v

` a bushingy 100 v,Within the head and an oil hole101. The base 97 has openings 102 for the passage of holdfast devices 103 to lixedlyl secure the bearing to the platform 4.

The stops or holders 94,95, 96 are threaded into the platform 4 and carry holding nuts 104. The pan 7 9 is common to the said several members 78 and has inset portions 105 for the nuts 104. See Figure 2. The pan 7 9 is furthermore provided With openings 106 for the passage of the grinder mechanisms. The collars 80 are flush with the edges of the openings 106. The latches 9 are pivoted on the enlarged cylindrical part-s 107 of the shanks of the holdfast devices 15. See F igure 3. The plate 16 has a grease cup 108 attached thereto which opens into the inner side of the journal 25 of the gear 25. Oil holes 109 are provided for the ends ofthe connecting rod 29. A dust collar 1'10is mounted on pin 39 and betvveenthe latter and casting 38. See Figure 5.

1n operation, power is applied to the gear Wheel 25 causing it to rotate and impart a reciprocatory motion tothe rack bar 32 and as the latter meshes with the pinions 61 these latter are turned through an angle slightly greater than 360o and then reversed and turned in the opposite direction as the rack bar reciprocates. By vmeans of the clutches the toothed ends of the hubs of the pinions 61 areengaged and cause the spindles to rotate as an integral part of the pinions. It is' evident then that by engaging or disengaging the clutches each spindlel may be operated independently of the others, and started or stopped at the Will of the operator.

At each half of a revolution of the gear 25 the cam surfaces 2 7 and 27 passover roller 41, depressing it and'causing the forked end of lifter to be raised, striking the valve body or housing and raising it from the valve. This admits grinding compound or abrasive material and oil into the valve and also prevents grinding grooves or irregular depressions in the valve parts. The amount of lift given the valve bodyor housing by the lifters is governed by the set screws 86 and is individually adjust-able for each valve. The valve body is prevented from rotating With the valve by means of the holders or stops 94, 95 and 96. 1 p

It is thought the many advantages of a grinding machine, for the purpose set forth can beV readily understood, and although the preferred embodiment of the invention is as illustrated and described, yet it is to be understoodthat changes in the details of construction can be had which Wall Within the scope of the invention as claimed.

What We claim is: i l 1. In a grinding. machine for the purpose set fort-h, the combination of a plurality of vertically disposed Work grinding mechanisms each including a driving pinion therefor above the lovver end thereof, a reciprocatory element common to said pinions for operating them, a driven gear carrying a crank pin on one side andhaving its other side provided with cam surfaces, a driving' connection between said pin and element, a lifter assemblyassociated with each mechanism for lifting the Work relative `to the latter during the `grinding action, a lifter shaft common to said assemblies for actuating them simultaneously to lift the work relative to said grinding mechanisms, and means extending `from one end of said shaft and successivelyengaged by said cam faces for intermittently rocking said shaft to provide for the intermittent actuation of said assemblies.

2. In a grinding machine for the purpose set' forth, the combination of a plurality of vertically disposed work grinding mechanismseach including a driving pinion therefor above the lower end thereof, a reciprocatory element common to said pinions for operating them, ai driven gear carrying a crank pin on one `side and having its other side provided with cam surfaces, a driving connection between said pin and element, a

lifter assembly associated with each mechanismfor lifting the work, relative to the latter during the grinding action, a lifter shaft common to said assemblies for actuatingthem simultaneously to liftthework relative to said grinding mechanisms, means eX- ;tending from one end of said shaft and successivelyengaged by said cam faces for intermittently rocking said shaft-to provide for the intermittent actuation of said assemblies, each of said assemblies including means for controlling theextent of the liftingaction 'thereofwith respect to the work.

3A. In a grinding machine for the purpose set forth, the combination of aA plurality of vertically disposed work grinding mechanisms each includinga` drivinglpinion therefor abovethe lower end thereof, a reciprocatory` element common to said pinionsffor operating'them, a driven gear carrying a crank pinonone side and having its other side provided with cam surfaces, a driving connection between said pin and element, a lifterassembly associated with each `mechanism for lifting the work relative to the latterduring the grindingaction, a lifter shaft LAt5 common to said assemblies for actuating them simultaneously to lift the work relative to said grinding mechanisms, means extending fromone end of said shaft and successively engaged bysaid 4cam faces for intermittently rocking said shaft to provide for the intermittent actuation of said assemblies, and means to provide for selectively discontinuing thefoperation of said grinding mechanisms fromthe driving pinions thereof.

4f In a grinding `machine for the purpose set forth, the combination of af plurality of vertically disposed work grinding `mecha-- nisms each including adriving pinion therefor above lthe lower end thereof, a reciprocatory element common to `said pinions `for operating them, a driven gear carrying a crank pin on one side and having its `other side provided with cam surfaces, a driving connection between said pin and element, a lifter assembly associated with each mechanism for lifting the work relative to the latter during the grinding action, a lifter shaft common to said assemblies for actuating them simultaneously to lift the work relative to said grinding mechanisms, saidmcans cxtending from one end of said shaft and successively engaged by said cam faces for intermittently rocking said `shaft to provide for the intermittent actuation of said assemblies, each of said assemblies including meansfor controlling the extent of the lifting action thereof with respect to the work, and means to provide for selectively discontinuing the operation ofsai d grinding mechanisn'isifrom the driving pistons thereof.

5. ln a grinding machine, a rotatable grinding mechanism including a drivingpinion therefor, a lifter assembly for liftingf the work relative to the grinding mechanism during the grinding action, said lifter assembly including a loosely mounted lifter arm and a combined adjusting and shifting means "for said arm, a rock shaft common to said arm and shifting means and having the latter fixed thereto, a reciprocatory rack bar for operating said pinion, a lever arm for operating said rock shaft, said arm carried by the rock shaft, and a rotatable element common to `said rack bar and lever arm for continuously operating the former and intermittently operating the latterto provide forf the intermittent operation of the rockshaft.

6. In a grinding machine, a rotatable grinding mechanism including a driving pinion therefor, said driving pinion being normally and loosely mounted relative to the other elements of the grinding mechanism, a lifter assembly associated with said mechanism for lifting the work relative thereto during thegrinding action on the work, said lifter i assembly including a loosely mounted lifter arm and a combined adjusting and shifting means for said arm, a rockshaft common to said arm and shifting `means and having the latter fixed thereto,a reciprocatory rack bar for operating said pinion, means for coupling'the pnion"in driving positionwit-h respect to said grinding mechanism Ato provide for the operation thereof, a leverarm carriedby and operating said rock shaft, and a rotatable `element common to said rack bar and lever arm for continuously operating the `former and `intermittently operating thelatter to provide respectively forthe operationof the pinion andthe intermittent `operation of the rock shaft.

` 7.111 a grinding machine, a `rotatable grinding i mechanism lfor the work, said mechanism including a driving piniontherefor, `a Ali fter -assembly associated with i said mechanism for lifting the work relative thereto during the grinding action on the work, said lifter assembly including` a loosely mounted lifter arm and a combined adjusting and shifting means for said arm, a rock shaft common to said arm and shifting' means vand having the latter fixed thereto, a r ciprocatory rack barfor operatingsaid pinion, a lever arm carried by said rock shaft and provided with a roller, and a rotatable element common to said racl bar and said roller for continuously operating the former and intermittently shifting the latter to providerespectively for the operation of said rack bar the intermittent opeiat'ionof Y said roclr shaft.

8. ln a grinding machine for the purpose set forth, a supporting structure, a plurality of spaced, vertically disposed work grinding mechanisms supported by and extending above said structure, each of said mechanisms including a grinding pinion therefor, a reciprocatory element slidably mounted in said structure and common to said pinions for operating them, said element provided intermediate its ends with an arm projecting outwardlyk from said structure, a combined gear and cam positioned adjacent one end of sail structure, an Voperative drive connection between said combined gear and cam and said arm to provide for the reciprocationof said element,a lifter assembly mounted on said structure and associated with each grinding mechanism and providing for lifting the work relative to the mechanism during the grinding action on theoworlr, a. lifter shaft supported over said structure and common tosaid assemblies for actuating them simultaneously, means carried by one endof said shaft and intern ittently operated from said combined gear and camjfor intermittentj ly rocking said shaft to provide for the actuation of Vsaid assemblies, and means for selectively controlling the operation vof said grinding mechanisms. i

` 9. In a grinding machine for the purpose set forth, a supporting structure, a plurality of spaced, vertically disposed work grinding mechanisms supported by and extending above said structure, each of said mechanisms including a grinding pinion therefor, a reciprocatory element slidablymounted in said structure and common to said pinions for operating them, said element provided intermediate its ends with an' arm projecting outwardly from said structure, acombined gear and campositioned adjacent one end of said structure, an operative drive connection between-said combined gear and cam and said arm tojprovide for the reciprocation of said element, a lifter assembly mounted on said structure and asociated with each grinding mechanism and providing for lifting the work relative to the mechanism during the grinding action on the work, a lifter shaft supported over said structure and common to said assemblies for actuating them simultaneously, means'v carried by one end of said shaft and intermittentlyoperated from said combined gear andr cam for intermittentlyroclring said shaft to provide for the actuation of said assemblies, means for selecsaid members extending into and discharging therein. j

lO.r A grinding machine for the purpose set forth, the combination of a supporting structure, a plurality of spaced, vertically disposed grinding mechanisms supported by and eX- tending above such structure, each of said mechanisms .including a driving pinion therefor above the lower end thereof, a reciprocatory element slidably mounted in said structure and common to said pinions for operating them, said element provided intermediate its ends with an armV projecting ontwardly from said structure, a driven combined gear and cam positioned-adjacent one end of said structure, a driving connection between said combined gear and cam and said arm to provide for the reciprocation of said element, lifter assemblies Vmounted on said structure and each associated with al grinding mechanism thus providing for lifting the workv being acted upon during the grinding action on the work, a liftershaft supported over said structure and vcommon to said assemblies for actuating them simultaneously, means projecting from one end of said shaft and intermittently engaged by said combinedgear and cam for intermittently rocking said shaftto provide for theactuation of said assemblies, and each of ysaid assemblies including means for controlling the extentof its movement. l

l1. Ak grinding machine for the purpose set forth, the combination of a supporting structure, a plurality of spaced, vertically disposed grinding mechanismV supported by and extending above suchstructure, each of said mechanisms including a driving pinion therefor above the lower endthereof, a reciprocatory velement slidably mounted in said structure and common to said pinionsy for operating them, said element provided intermediateits ends with an arm projecting outwardly from said structure, a driven combined gear and cam positioned adjacent one end of said structure, a driving connection between said combined gear and cam and said arm to provide for the reciprocation of said element, lifter assemblies mounted on said structure and each associated With a grinding mechanism thus providing for lifting the Work being acted upon during the grinding action on the work, a lifter shaft supported over said structure and common to said assemblies for actuating them simultaneously, means projecting from one end of said shaft and intermittently engaged by said combined gear and cam for intermittently rocking said shaft to provide for the aetnation of said assemblies, each of said assemblies includingl means for controlling the eX* tent of its movement, and means for selectively controlling the operation of said grindin@V mechanisms.

In testimony whereof, We'aiiix our signatures hereto.

REGINALD F. PETERS. GLENN L. DAVIS. 

